TIFF thumbnail previews not displaying with more than 5 channels

[DJClements]

Hi all,

So I have some photoshop files rendered from Cinema 4D with auto-generated masks and alpha channels for specific parts of the image. There are 7 channels in total. Whenever I try to save the file out as a TIFF, expecting there to be a thimbnail preview, there isn't one generated, but when I reduce the channels to 5 in total or less, the image preview appears as it should.

Does anyone have any idea what's going on?

Example files attached, "Test01" had 6 channels and does not preview on my machine, "Test02" has 5 channels and previews perfectly fine, using the first channel as the alpha in the thumbnail.

I am using Photoshop CC, fully updated, and running Windows 10.

[davescm]

I suspect the problem/limitation lies with Windows not Photoshop, although I'd not noticed it before. Both examples preview in Bridge and open in Photoshop.
The six Alpha channel version neither previews in File Explorer or opens in Windows Photo Viewer. I repeated it by adding Alpha channels to my own file and found the same.

Dave

[DJClements]

Thanks for taking a look davescm, this is the first time I'd found a cause of this, as it has happened in the past. I will simply have to keep my alpha channels to a minimum!

[Marianne-Deiters]

On my Mac it is not a problem, the preview is displayed correctly.

[DJClements]

Thank you for your response Marianne-Deiters, this confirms the problem is most likely a Windows issue.